In order to remotely drill or mill a hole in a pipe wall using an in-pipe device the drill bit must be aligned at right angles to the axis of the pipe and a means of reacting the load exerted on the drill against the pipe wall must be provided. Most existing in-pipe machines are designed to operate in pipes sufficiently large that the inclusion of a separate actuator specifically to provide a reaction support is feasible. In smaller pipes such an actuator is difficult to accommodate, therefore there was a need to consider an alternative approach.